It is possible to print electronic circuits using familiar printing techniques such as ink jet printing. A printhead can deposit circuit materials similarly to how it would deposit ink onto a surface. A circuit or component designer provides the layout of the circuit or component to the printer and the printer forms the circuit or component on a circuit substrate using printing techniques.
For purposes of discussion here, circuits, generally a collection of electronic components in electrical connection with each other, and components, individual electronic structures, will be referred to as circuits. Similarly, a printer would be any type of fluid dispensing system that can deliver liquids suitable for forming circuits based upon some layout or direction for forming the circuit. A circuit substrate may be any carrier or other surface upon which the circuit is formed.
Formation of electronic circuits with printing techniques may have issues with exact definition of structures due to surface tension effects in the dispensed liquid, inaccurate drop placement, or because of the rounded edges of current printed structures. Lines are not exactly straight, with visible scalloping from placement of the individual drops, and squares or rectangles have rounded edges. It is also difficult to print narrow lines and narrow spaces. These problems result in variations in the formations of the circuits. Variations in the formation of the circuits may result in variations in the circuit performance.
In one example of problems caused by variations in the formation of the circuits, displays produced using printed circuits may have variations in the charging times (RC charging time) for the addressing of the pixels in the display. These variations cause differences between pixels in the resulting image, especially in gray scale images. In gray scale images, the resulting gray level of a pixel depends upon how long the pixel is active within a particular period of time. Variations in how long it takes a pixel to charge cause variations in the gray level that are undesirable and uncontrolled, degrading image quality.